Oil still



Dec. 22, 1925- J. PRIMROSE OIL STILL Filed June 19 1920 v- W ATTOR 5V8 8) [WW 1 I 7% Patented Dec. 22, 1925.

UNITED STATES 1,566,921 PATENT OFFICE.

JOHN PRIMROSE, OF NEW YORK, N. Y., ASSIGNOR TO' POWER SPECIALTY COMPANY,

OF YORK, N- Y-, A CORPORATION OF NEW YORK.

OIL s'rILL.

Application filed June 19, 1920., Serial No. 390,088.

To all whom it may concern:

Be it known that I, Join: PRIMROSE, a citizen of the United States, residing at New York, in the county and State of New York, have invented certain new and useful Im-- provements in ()il Stills, of which the following is a full, clear, and exact description.

.by a vertical bridge wall into two compartments. In that which is the more remote from the fire the heatabsorbing tubes or pipes carrying the oil are arranged in one main group, over which the hot gases flow downwardly, While the oil, introduced cold at the bottom of the bank, flows counter to the current of hot gases. After passing through this bank of tubes the hot oil is carried over to-the bottom of a smaller bank of tubes in the compartment over the fire, and the top of such bank is connected to the usual se arator for taking off the vapors set free by the 'heat and delivering the unvaporized oil to a suitable receptacle.

This form of still is described merely as typical of all stills to which my imprpvement is applicable, and in such stills it has been found that the oil in the final heat absorption stage, or in the second bank of coils where it is exposed to the highest temperature, does not give off all of the vapors which it should, but-thatka certain proportion of its volatile constituents goes over to the separator w'th the oil.

It is to reme y this objection and to increase the yield of the volatile constituents of the oil that Iriy present improvement was devised, and it consists in providing a return passage for unvolatilized oil from the separator to the said second bank of tubes, and providing means for forcing oil to flow through said bank a second time, whereby the unvolatilized parts thereof will be driven off by such second or repeated heating and a lar r output of vapor thus obtained.

'ggecifically considered, the construction of the still is not of the essence of the invention, provided the condition herein described obtains, and the invention is not therefore limited in its scope, but consists broadly in the combination with the hottest elemcnts of the heating surface of means for returning and forcing through the same the uuvaporizcd oil or any desired portion of the same which has already passed through them.

The invention is illustrated in the accompanying drawing, which is a view largely diagrammatic of a still of the kind described with my invention applied thereto.

The heating chamber 1 of the still is of the usual character, and is, in the present i11- stance, divided by a vertical wall 2 into a forward and a rear compartment. In the latter is a bank of oil tubes or pipes 3 connected in any proper and known manner for causing the oil from the source of supply 4 to flow upward through the tubes of the bank or in a direction counter to the How of the hot gases which pass downward in this compartment on their way to the flue.

In the forward compartment is a second and smaller bank 5 of'oil tubes, the lowermost row of which is connected with the uppermost row in the first bank, and such smaller bank is connected by a pipe 6 to any suitable form of separator 7. The flow of oil in the second bank is not, and need not be,

counter to the flow of gases, as the oil has reached a temperature when it enters the second bank that makes this unnecessary for good results.

From the separator the vapors are taken off, as by means of a pipe 8, and the unvolatilized oil by a pipe 9 at the bottom, but by means of apipe 10 any proportion of this oil that may be desired or found necessary is led to a pump 11, by which it is forced back to the connection 12 between the first and second banks of tubes, and hence caused to flow again through the hottest tubes, or those of the smaller second bank.

By this means it has been found that much Va or that is not given off by the first run of Oll is set free on its subsequent travel through the second hot bank.

Manifest-1y the construction of the still as a whole is largely immaterial. As is usual in practice, it will be provided with the proper controlling valves, with means for indicating the temperature of the oil and other known accessories.

- What I claim is:

1. The combination with an oil still hav" ing banks or groups of tubes exposed to the passed through the still, for the purpose set v forth.

2. The combination with'an oil still, of a furnace comprising two compartments, a

bank of tubes in that compartment more remote from the fire, a bank of tubes in the compartment nearer the fire connected in series with the first, and means including an oil supplying connection intermediate the first and second banks for forcing oil that has passed through and issued from the second bank back to and through said bank, for the purpose set forth.

3. The combination with an oil still hav ing two banks of tubes and means for causing-the oil to flow counter to the hot gases in the bank which is the more remote from the fire, of a separator connected with the bank which is nearer the fire, a connection for oil from the separator back to the second bank and a pump therein for causing oil after having passed through said second bank and separator to reflow through the second bank, for the purpose set forth.

at. The combination with an oil still having two banks of tubes, one near the fire and the other more remote therefrom, means for causing the oil to flow counter to hot gases in the latter bank and in the direction of the passage of the hot gases in the former bank, a separator connected with the outlet of the bank nearest the fire, and means for causing oil to flow back from the separator to the inlet of said former bank, said means being independent of the oil supplying means for the said latter bank.

in testimony whereof I hereto affix my signature.

JOHN PRIMROSE. 

